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Discussion Starter #1
Is there any real difference in the way headers are designed? I'm seein' 4-1, 4-2-1, Tri-Y (which is the the same as 4-2-1 if I'm not mistaken) and others. Is there a "better" header, or is it just a matter of preference? I've heard from the Honda guys that one type gives more torque, the other type gives more horsepower.. but that makes no sense at all (maybe more power at different parts of the powerband?). Can someone clear this up? *looks around for Geo* :p
 

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I'm not too sure on which gives what but the difference in design affects the horsepower & torque at certain RPM range ....such as low-end, mid-range, top-end RPM are all affected by the design of the header... now as to which design affects what I'm not sure... anybody else wish to elaborate alittle bit more clearly?
 

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FF Drifter said:
Is there any real difference in the way headers are designed? I'm seein' 4-1, 4-2-1, Tri-Y (which is the the same as 4-2-1 if I'm not mistaken) and others. Is there a "better" header, or is it just a matter of preference? I've heard from the Honda guys that one type gives more torque, the other type gives more horsepower.. but that makes no sense at all (maybe more power at different parts of the powerband?). Can someone clear this up? *looks around for Geo* :p

Tri Y and 4-2-1 are indeed the same.

Headers have a resonsant frequency where at certain rpm they opperate at their best. Wave reflections compliment each other (can't remember the correct expression at the moment) and the header becomes more effective than "normal." With a 4-1 header there is one frequency where this happens and it is more intense. With the 4-2-1 there are two and they are less intense. If someone here knows fluid dynamics, they can probably explain it better in technical terms than I can right now.

Typically what is expected is that the 4-1 will make more peak power, but have a more narrow power band and the 4-2-1 will make a bit less power but will have a much broader power band.

That is the theory. In practice it doesn't always work that way. When SCC did their SR20DE header test, the Hotshot (4-2-1) made more peak power over a slightly narrower range than the AEBS (4-1). Just the opposite of what was expected. Go figure.
 

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Discussion Starter #4
Okay thanks a lot for clearing that up. I always thought it was out of laziness or something that they made 4-1 headers, or maybe the were lighter or something...*by 0.2lbs or something?* Haha ok thanks a lot though. :p

Oh, and single piece headers are better than two-piece, I assume? Maybe harder to install, but better somehow?
 

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FF Drifter said:
Oh, and single piece headers are better than two-piece, I assume? Maybe harder to install, but better somehow?
I think it goes like this....
A single piece header will be lighter and you won't have to worry about it leaking at the primary to secondary connection. Also in a low quality 2 peice header the two peices might not line up exactly disrupting flow. However, a one piece header will be tougher to install (in most cases, definitely in the case of our cars).
 
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